ocPortal is a free Content Management system for advanced dynamic/interactive websites.
From the Author
ocPortal is a CMS with many Web 2.0 and community features, for building modern, sophisticated websites. ocPortal supports many types of content (galleries, news/newsletters, etc.) - and integrating rich media and advertising into them. Community features include forums, member blogs, chat rooms, WIKI, and content commenting/rating. ocPortal lets you decide how your site will look and behave. Features are plentiful, but also optional. Feature integration is at the core of the ocPortal philosophy - for example, the site-wide search engine, and the unified member profiles. Out-of-the-box your site will meet the highest accessibility and professional standards, and will appear higher in Google due to automatic SEO. Your website will automatically block and record hacking attempts, and you can control access in different ways such as via paid subscription. ocPortal is designed as the software that'll handle all your needs; you'll get much more than just a Content Management System.
Authors website: http://ocportal.com/